Police Service of Northern Ireland (PSNI) Chief Constable Matt Baggott was speaking after another weekend of violence following flag protests.

Mr Baggott described the disorder in Cloughfern, Carrickfergus and east Belfast on Friday and Saturday as intense, and warned those involved to expect a knock at the door.

"Our approach has always been to be measured and responsible," he said.

"We have simply to put public safety first. That has worked very well and continues to work well. Pragmatically, when you have over 4,000 people engaged in protest it is simply impossible to have a rigid approach to that. What we are keen to do is to keep hospitals and arterial routes open and are continually revising our tactics.

"There is speculation about why doesn't the PSNI do this. The reality is we make sure that people's rights for peaceful protest are upheld wherever possible and we preserve our resources for dealing with the most serious outbreaks of violence."

On Saturday violence broke out in east Belfast between republicans and loyalists returning from a protest at Belfast City Hall over a council decision to restrict the flying of the Union flag there. To date, 101 police officers have been injured during the rioting, one of whom remains in hospital. There have been 112 arrests connected to the disorder.

The chief constable stopped short of saying that the PSNI would move flag protesters off the streets. Mr Baggott added: "I think there is a reality check about the role of policing in a democracy. Unless you are going to literally have tens of thousands of police officers, probably backed up by the military covering every street in Northern Ireland, you cannot deal with this simply by law enforcement approach.

"Policing is all about the consent of the public and working with politics and at the moment that is the bit that needs to be reasserted. What I can do, in charge of this fantastic organisation, is to make sure that we give space for the politics to work."

Mr Baggott also said criminal gangs in working class loyalist areas were exploiting young protesters for their own ends. He added: "They were leading young people by the nose towards prison."